[PATCH] i2c: bcm2835: Fix an error handling path in 'bcm2835_i2c_probe()'

From: Christophe JAILLET
Date: Tue May 05 2020 - 09:10:06 EST


A call to 'clk_set_rate_exclusive()' must be balanced in the error handling
path.
Add a corresponding 'clk_rate_exclusive_put()'.

While a it, also balance a 'clk_prepare_enable()' call with a
'clk_disable_unprepare()' call and move a 'free_irq()' to the new error
handling path.

This has the side effect to propagate the error code returned by
'request_irq()' instead of returning -ENODEV.

This way, the error handling path of the probe function looks similar to
the remove function.

Fixes: bebff81fb8b9 ("i2c: bcm2835: Model Divider in CCF")
Signed-off-by: Christophe JAILLET <christophe.jaillet@xxxxxxxxxx>
---
drivers/i2c/busses/i2c-bcm2835.c | 18 ++++++++++++++----
1 file changed, 14 insertions(+), 4 deletions(-)

diff --git a/drivers/i2c/busses/i2c-bcm2835.c b/drivers/i2c/busses/i2c-bcm2835.c
index d9b86fcc3825..7f403e07dff4 100644
--- a/drivers/i2c/busses/i2c-bcm2835.c
+++ b/drivers/i2c/busses/i2c-bcm2835.c
@@ -451,13 +451,14 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
ret = clk_prepare_enable(i2c_dev->bus_clk);
if (ret) {
dev_err(&pdev->dev, "Couldn't prepare clock");
- return ret;
+ goto err_unprotect_clk;
}

irq = platform_get_resource(pdev, IORESOURCE_IRQ, 0);
if (!irq) {
dev_err(&pdev->dev, "No IRQ resource\n");
- return -ENODEV;
+ ret = -ENODEV;
+ goto err_unprepare_clk;
}
i2c_dev->irq = irq->start;

@@ -465,7 +466,7 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)
dev_name(&pdev->dev), i2c_dev);
if (ret) {
dev_err(&pdev->dev, "Could not request IRQ\n");
- return -ENODEV;
+ goto err_unprepare_clk;
}

adap = &i2c_dev->adapter;
@@ -483,7 +484,16 @@ static int bcm2835_i2c_probe(struct platform_device *pdev)

ret = i2c_add_adapter(adap);
if (ret)
- free_irq(i2c_dev->irq, i2c_dev);
+ goto err_free_irq;
+
+ return 0;
+
+err_free_irq:
+ free_irq(i2c_dev->irq, i2c_dev);
+err_unprepare_clk:
+ clk_disable_unprepare(i2c_dev->bus_clk);
+err_unprotect_clk:
+ clk_rate_exclusive_put(i2c_dev->bus_clk);

return ret;
}
--
2.25.1